1. Field of the Invention
Aspects of the present invention relate to a method and apparatus of providing a panoramic view, and more particularly, to a method and apparatus for providing a panoramic view, in which a processing speed of image stitching is improved and an image is smoothly stitched with respect to a color blending to provide the panoramic view. Also, the method and apparatus may be applied to other fields of stitching images and acquiring an expanded image as well as providing the panoramic view.
2. Description of the Related Art
Currently, when providing a location-based service using a popularized navigation system, a portable device, a personal digital assistant (PDA), etc., more realistic image information may be provided based on a real scene with respect to a service providing area.
As an example, as shown in FIG. 1, as a vehicle moves in the direction of A→B→C, image information for showing the way needs to change from surrounding images 111 that were taken with a rotating camera on a tripod 110 at a location X into surrounding images 121 that were taken on a tripod 120 at a location Y.
As described above, to provide the images photographed by the camera at several locations, to a predetermined system of a user receiving a location-based service in a vehicle, images of each location are stitched together at a part of each image containing the same location, as shown in 210 of FIG. 2, to form one panoramic image as shown in 220 of FIG. 2.
In an image stitching technique for providing a panoramic image, images photographed from many places or locations are gathered together and attached on a virtual cylinder to be registered in a system. For example, as shown in 210 of FIG. 2, generally two images that are overlapped with each other by ¼ to ¾ (25 to 75%) of a width and by 0 to ⅛ (0 to 12.5%) of a height are adjusted to detect a location in which a sum of square difference (SSD) of image data is a minimum. Namely, at the location in which a difference between the two image data is a minimum, the two images are stitched as shown in 220 of FIG. 2, thereby completing a panoramic image.
However, in the conventional image stitching technology as described above, a high overhead occurs due to a large amount of SSD computations. Namely, as described above, since, with respect to the two source images, a data amount of ¼ to ¾ of a width (or a horizontal area) and a data value of 0 to ⅛ of a height (or a vertical area) have to be mutually compared, there is a great load on a processing apparatus such as computation time, memory, bandwidth, or other resources.
Also, in the image stitching described above, although there may be the same images in the parts of the two overlapping images, a great difference may exist in color information due to a difference between environments from which photographs are acquired. In this case, the two images are smoothly connected with each other by blending colors in the overlapped part. For example, in FIG. 3, when a first image 310 having a width A to C is connected with a second image 320 having a width B to D, with respect to parts B to C of the two overlapping images, linear weights W1 and W2 are respectively applied to both image data to be processed. However, in the image blending technology described above, there are many cases of providing unnatural panoramic images due to abrupt color change of two images.